1. Field of the Invention
This invention relates to a vehicle and more particularly to a railway vehicle.
2. Description of the Prior Art
On a similar railway vehicle of the prior art (DE 42 34 553 A1), between a car body and a truck located underneath it there is a connecting device that has a hydraulic actuator with a piston and a cylinder housing as an adjustment means that can be adjusted axially only in a straight line in relation to one another. The cylinder housing and the piston or the piston rod connected to the piston are each provided with a single-axis knuckle joint, whereby one knuckle joint is coupled with the car body and the other knuckle joint is coupled in an at least a largely perpendicular orientation underneath it to the undercarriage frame of the truck. The actuator is thereby used to control the level of the car body. One disadvantage of this design is that in the event of a failure of a hydraulic and/or pneumatic system, special support elements must be provided, which completely relieve the actuators which are fastened flexibly on both ends, because without additional support means, these actuators can tip around the knuckle connector, as a result of which there can be an unacceptable displacement of the car body with respect to the undercarriage.
The object of the invention, on a railway vehicle, is to take measures so that the connecting means also perform the necessary support function even in the event of malfunctions or failures of other systems.
The invention has a car body supported by a truck with an undercarriage.
In one configuration of a vehicle as claimed by the invention, a connecting device forms a support mechanism, on which the actuator can always be kept in a perpendicular orientation with respect to one of the two vehicle parts. Rotational and displacement movements between the horizontal plane formed by the truck frame and the plane formed by the underside of the car body, on the other hand, are equalized by knuckle connectors having the characteristic of a ball-and-socket joint and sliding connectors. The sliding connectors for each connecting device thereby have degrees of freedom in translation only in a plane that runs parallel to the plane to which the connecting element or elements are fastened. The connecting devices thereby stand perpendicular to the plane on which they are fastened. In the event of the failure of the actuator that is realized in the form of a hydraulic cylinder, an electrically driven spindle system or a similar mechanism, the actuator can therefore not rotate with respect to the vehicle part to which it is fastened. Consequently, in any case, the minimum axial length of the actuator determines the distance between the vehicle parts that must be kept at a distance from one another and that can move within specified limits with respect to one another. The necessary rotational movements are thereby absorbed by the knuckle joint that is integrated into the connecting device. In this case, the knuckle connector can be realized in the manner of a universal joint or a ball-and-socket joint, while the movement of the sliding connector in translation can be restricted to the magnitude necessary for the operation of the railway vehicle by the attachment of corresponding stops. The connecting device thus consists of a mechanical-functional series arrangement that consists of the actuator, a sliding connector that can be adjusted only in one plane and a knuckle connector that is realized in the manner of a ball-and-socket joint. This connecting device includes, in the form of the changeable-length actuator, an element for the simultaneous limitation of the vertical distance between the undercarriage and the car body, and in the form of the restricted-motion sliding connector, a functional element, the sole purpose of which is to restrict the movement between the two vehicle parts in the direction of the vehicle travel or at a right angle to the direction of travel. The knuckle connector also allows only the inclinations or torsion between the planes described by the vehicle parts that occur during operation.
When the connecting device that is realized in the form of a support and interface between the undercarriage and the car body consists of three components, each of which makes possible different degrees of freedom for the movement between the vehicle parts, movable elements of two of the components can each be connected rigidly with the two vehicle parts, so that the third component always forms the connecting element between the second adjustable elements of the fastened components. In all cases, only the reciprocating movement of the respective actuator is available for the vertical adjustment between the undercarriage and the car body, and only by a maximum of this reciprocating distance can the car body descend toward the undercarriage, because neither the knuckle connector nor the sliding connector allows a movement in this direction, and the longitudinal axis of the actuator cannot be tipped with respect to one of the vehicle parts.